#include <ddk.h>
#include <linux/errno.h>
#include <mutex.h>
#include <pci.h>
#include <syscall.h>
LIST_HEAD(pci_root_buses);
#define IO_SPACE_LIMIT 0xffff
#define PCIBIOS_SUCCESSFUL 0x00
struct resource ioport_resource = {
.name = "PCI IO",
.start = 0,
.end = IO_SPACE_LIMIT,
.flags = IORESOURCE_IO,
};
struct resource iomem_resource = {
.name = "PCI mem",
.start = 0,
.end = -1,
.flags = IORESOURCE_MEM,
};
#define PCI_FIND_CAP_TTL 48
static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
u8 pos, int cap, int *ttl)
{
u8 id;
while ((*ttl)--) {
pci_bus_read_config_byte(bus, devfn, pos, &pos);
if (pos < 0x40)
break;
pos &= ~3;
pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
&id);
if (id == 0xff)
break;
if (id == cap)
return pos;
pos += PCI_CAP_LIST_NEXT;
}
return 0;
}
static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
u8 pos, int cap)
{
int ttl = PCI_FIND_CAP_TTL;
return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
}
static int __pci_bus_find_cap_start(struct pci_bus *bus,
unsigned int devfn, u8 hdr_type)
{
u16 status;
pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
if (!(status & PCI_STATUS_CAP_LIST))
return 0;
switch (hdr_type) {
case PCI_HEADER_TYPE_NORMAL:
case PCI_HEADER_TYPE_BRIDGE:
return PCI_CAPABILITY_LIST;
case PCI_HEADER_TYPE_CARDBUS:
return PCI_CB_CAPABILITY_LIST;
default:
return 0;
}
return 0;
}
/**
* pci_find_capability - query for devices' capabilities
* @dev: PCI device to query
* @cap: capability code
*
* Tell if a device supports a given PCI capability.
* Returns the address of the requested capability structure within the
* device's PCI configuration space or 0 in case the device does not
* support it. Possible values for @cap:
*
* %PCI_CAP_ID_PM Power Management
* %PCI_CAP_ID_AGP Accelerated Graphics Port
* %PCI_CAP_ID_VPD Vital Product Data
* %PCI_CAP_ID_SLOTID Slot Identification
* %PCI_CAP_ID_MSI Message Signalled Interrupts
* %PCI_CAP_ID_CHSWP CompactPCI HotSwap
* %PCI_CAP_ID_PCIX PCI-X
* %PCI_CAP_ID_EXP PCI Express
*/
int pci_find_capability(struct pci_dev *dev, int cap)
{
int pos;
pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
if (pos)
pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
return pos;
}
static struct pci_bus * pci_alloc_bus(void)
{
struct pci_bus *b;
b = kzalloc(sizeof(*b), GFP_KERNEL);
if (b) {
INIT_LIST_HEAD(&b->node);
INIT_LIST_HEAD(&b->children);
INIT_LIST_HEAD(&b->devices);
INIT_LIST_HEAD(&b->slots);
INIT_LIST_HEAD(&b->resources);
}
return b;
}
struct pci_bus * pci_create_bus(int bus, struct pci_ops *ops, void *sysdata)
{
int error;
struct pci_bus *b, *b2;
b = pci_alloc_bus();
if (!b)
return NULL;
b->sysdata = sysdata;
b->ops = ops;
b2 = pci_find_bus(pci_domain_nr(b), bus);
if (b2) {
/* If we already got to this bus through a different bridge, ignore it */
dbgprintf("bus already known\n");
goto err_out;
}
// down_write(&pci_bus_sem);
list_add_tail(&b->node, &pci_root_buses);
// up_write(&pci_bus_sem);
b->number = b->secondary = bus;
b->resource[0] = &ioport_resource;
b->resource[1] = &iomem_resource;
return b;
err_out:
kfree(b);
return NULL;
}
static struct pci_bus *pci_do_find_bus(struct pci_bus *bus, unsigned char busnr)
{
struct pci_bus* child;
struct list_head *tmp;
if(bus->number == busnr)
return bus;
list_for_each(tmp, &bus->children) {
child = pci_do_find_bus(pci_bus_b(tmp), busnr);
if(child)
return child;
}
return NULL;
}
/**
* pci_find_bus - locate PCI bus from a given domain and bus number
* @domain: number of PCI domain to search
* @busnr: number of desired PCI bus
*
* Given a PCI bus number and domain number, the desired PCI bus is located
* in the global list of PCI buses. If the bus is found, a pointer to its
* data structure is returned. If no bus is found, %NULL is returned.
*/
struct pci_bus * pci_find_bus(int domain, int busnr)
{
struct pci_bus *bus = NULL;
struct pci_bus *tmp_bus;
while ((bus = pci_find_next_bus(bus)) != NULL) {
if (pci_domain_nr(bus) != domain)
continue;
tmp_bus = pci_do_find_bus(bus, busnr);
if (tmp_bus)
return tmp_bus;
}
return NULL;
}
/**
* pci_find_next_bus - begin or continue searching for a PCI bus
* @from: Previous PCI bus found, or %NULL for new search.
*
* Iterates through the list of known PCI busses. A new search is
* initiated by passing %NULL as the @from argument. Otherwise if
* @from is not %NULL, searches continue from next device on the
* global list.
*/
struct pci_bus *
pci_find_next_bus(const struct pci_bus *from)
{
struct list_head *n;
struct pci_bus *b = NULL;
// WARN_ON(in_interrupt());
// down_read(&pci_bus_sem);
n = from ? from->node.next : pci_root_buses.next;
if (n != &pci_root_buses)
b = pci_bus_b(n);
// up_read(&pci_bus_sem);
return b;
}
/**
* pci_get_slot - locate PCI device for a given PCI slot
* @bus: PCI bus on which desired PCI device resides
* @devfn: encodes number of PCI slot in which the desired PCI
* device resides and the logical device number within that slot
* in case of multi-function devices.
*
* Given a PCI bus and slot/function number, the desired PCI device
* is located in the list of PCI devices.
* If the device is found, its reference count is increased and this
* function returns a pointer to its data structure. The caller must
* decrement the reference count by calling pci_dev_put().
* If no device is found, %NULL is returned.
*/
struct pci_dev * pci_get_slot(struct pci_bus *bus, unsigned int devfn)
{
struct list_head *tmp;
struct pci_dev *dev;
// WARN_ON(in_interrupt());
// down_read(&pci_bus_sem);
list_for_each(tmp, &bus->devices) {
dev = pci_dev_b(tmp);
if (dev->devfn == devfn)
goto out;
}
dev = NULL;
out:
// pci_dev_get(dev);
// up_read(&pci_bus_sem);
return dev;
}
/**
* pci_find_ext_capability - Find an extended capability
* @dev: PCI device to query
* @cap: capability code
*
* Returns the address of the requested extended capability structure
* within the device's PCI configuration space or 0 if the device does
* not support it. Possible values for @cap:
*
* %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
* %PCI_EXT_CAP_ID_VC Virtual Channel
* %PCI_EXT_CAP_ID_DSN Device Serial Number
* %PCI_EXT_CAP_ID_PWR Power Budgeting
*/
int pci_find_ext_capability(struct pci_dev *dev, int cap)
{
u32 header;
int ttl;
int pos = PCI_CFG_SPACE_SIZE;
/* minimum 8 bytes per capability */
ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
return 0;
if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
return 0;
/*
* If we have no capabilities, this is indicated by cap ID,
* cap version and next pointer all being 0.
*/
if (header == 0)
return 0;
while (ttl-- > 0) {
if (PCI_EXT_CAP_ID(header) == cap)
return pos;
pos = PCI_EXT_CAP_NEXT(header);
if (pos < PCI_CFG_SPACE_SIZE)
break;
if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
break;
}
return 0;
}